Would an impossibly bow-legged bird perched on dist. line be electrocuted?

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Wbren75

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I've had a bit of an argument with someone over a video which I will link below.

In the video, a man is standing on top of a boat which is loaded on a tractor trailer. His job appears to be lifting low-hanging cables which otherwise wouldn't clear the top of the boat as the tractor drives down a street. Everything seems to be going fine until he grabs the cable with his other (free) hand, after which he suffers an apparently severe shock. The argument I was involved in was a dispute over what it was that shocked him. Another cable can be seen above the man's head, and from the perspective of the observer, it appears to be directly over his head. Not only that, but the shock occurs almost exactly at the moment when the observer's view of the cable is obstructed by the man's head. However, looking at the delta of vertical distance between the utility pole connections of the two cables, it seems to me to be impossible for the topmost cable to be anywhere near his head unless it had an absurd amount of sag.

I'm having a difficult time rationalizing what else could have caused the shock, and that's the genesis of this ridiculous thread title. Since the shock occurred very shortly after he grabbed the cable with his second hand, I wondered if the potential difference between two points (roughly a meter) on a single HV cable could be great enough to cause a severe shock. Alternatively, if instead of an incredibly small distance (less than an inch?), a bird's feet while perched on a distribution line were separated by a meter, would it be turned into a crispy critter?

Any speculation about what happened in the video is obviously wholly welcomed. I am convinced that the topmost cable couldn't possibly be close enough to come into contact with this man's head.

DISCLAIMER: IN THIS VIDEO, A MAN IS SEEN SUFFERING A SEVERE ELECTRIC SHOCK, POSSIBLY ELECTROCUTION. VIEWER DISCRETION IS ADVISED.
https://www.documentingreality.com/...arrying-boat-lifts-high-tension-wires-194702/
 
My guess would be that he was not adequately insulated through his shoes and the current path was through the boat and the trailer to ground
 
It rather looks like the wire being lifted itself contacted a different wire. Not the wire that is high overhead, but a lower wire that crosses.

It is very unlikely that the potential difference along a short length of even EHV conductor would cause shock (remember the lineworkers who get dropped onto EHV lines from helicopters for maintenance). But the voltage between medium voltage distribution and ground is easily fatal, and the worker was standing on a non-insulated structure.

Also it isn't clear that the worker was lifting a single line, rather it looks like a triplex cable of the sort used to bring power into a home. This might be two insulated 'hot' wires and a bare 'neutral' wire. If the wire has bad insulation (easily the case sitting undisturbed in the air) then someone could grab the 'hot' wire and the 'neutral' wire, and get a 120V shock with no contact with anything else.

-Jon
 
Agree that it looks like triplex secondary. Insulation could have been deteriorated and grabbing on caused a short.
 
winnie said:
It is very unlikely that the potential difference along a short length of even EHV conductor would cause shock (remember the lineworkers who get dropped onto EHV lines from helicopters for maintenance). But the voltage between medium voltage distribution and ground is easily fatal, and the worker was standing on a non-insulated structure.

-Jon
Click to expand...

I agree with above.

IMHO-
The arc is too large to be 120/240 but it could be the bare messenger wire in there contacting the other line in the video which may have been a single phase of distribution voltage. I suppose the boat must have been grounded enough???
 
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